Do the UPB switches offer firmware upgrade capability? Being realistic, this isn't something I'd expect in a hardwired, relatively low cost device? Yes, I can see the need for it, but if SH wants to protect their intellectual property, that's hard to do if you start giving even dealers the firmware files (which by their nature cannot be encrypted or protected).
SwitchLincs can be flashed to the latest firmware, Smarthome frequently does this with on hand stock before shipping. So far they have been unwilling to provide a means for dealers or end users to do it; probably for the "intellectual property" reasons you noted. A good alternative might be to have the ROM chip socketed and accessible under the paddle so it could be swapped without uninstalling the switch.
It seems to me, SH is pushing Insteon in the DIY small scale retrofit direction rather than towards serious whole house automation to compete with UPB, etc?
It is hard to understand what Smarthome's marketing strategy is at this point. If they were focusing on retrofit they would be more aggressive in developing things like screw-in modules and surface mount wall controllers. If it was just DYI then an RF remote would have been available from day 1. If it was the professional installer market there would have been programming software and a ROM upgrade strategy right from the start. It appears they are focusing on a special, secret market segment that only exists in the minds of their marketing execs.